The present invention relates to a tripod, and more specifically to the positioning arrangement of a holder frame at a center post in a tripod.
FIG. 1 shows a tripod for holding a camera according to the prior art. The tripod 10 comprises a shell 11, a center tube 12 mounted in the shell 11, three legs 13 pivoted to the shell 11, a sliding ring 14 moved along the center tube 12, three links 15 respectively coupled between the sliding ring 14 and the legs 13, a tubular center post 16 moved in the center tube 12 and locked by an elevator lock (not shown), the center post 16 having a longitudinal rack 161 meshed with an elevation adjustment gear at the shell 11, a socket 20 mounted on the top end of the center post 16, a holder frame 30 fastened to the socket 20 by a screw cap 21, and a platform 50 mounted on the holder frame 30 for holding a camera. The socket 20 is fixedly secured to the top end of the center post 16, and the screw cap 21 is threaded into the socket 20 to secure the holder frame 30 in place. If the screw cap 21 is not tightly fastened up, the screw cap 21 and the holder frame 30 may fall from the socket 20. Further, the threads of the screw cap 21 wear quickly with use. When the threads of the screw cap 21 start to wear, the screw cap 21 cannot be fastened to the socket 20 tightly.